Venoclysis equipment



March 22, 1955 ca. R. RYAN VENOCLYSIS EQUIPMENT E5 Sheets-Sheet 1Original Filed Oct. 5, 1949 Fis. III

Inuen for George 1?. Ryan Q, MM. M

0ffown ey March 22, 1955 e. R. RYAN VENOCLYSIS EQUIPMENT 3" $heets-Sheet2 Original Filed Oct. 5, 1949 I, Inllln ll Ialll. i. v

Invenzor George R. Egan {.9 wmw fiforneg March 22, RYAN VENOCLYSISEQUIPMENT Original F iled Oct. 5, 1949 3 Sheets-Sheet 3 Jrm/efifor Cieozge R. Ryan 29 W4 2% VENOCLYSIS EQUIPMENT George R. Ryan, WaukeganTownship, Lake County, Ill., assignor to Abbott Laboratories, NorthChicago, III., a corporation of Illinois Continuation of applicationsSerial No. 119,645, October 5, 1949, and Serial No. 128,549, November21, 1949. This application July 3, 1953, Serial No. 365,826

28 Claims. (Cl. 128-214) My invention relates to medical equipment andincludes among its objects and advantages improved means foradministering blood plasma and other fluids intravenously. In theaccompanying drawings:

Figure I is a vertical sectional view of a device according to theinvention;

Figure II is the plan view of the device of Figure I;

Figure III is a vertical sectional view of a modified device accordingto the invention;

Figure IV is a vertical sectional view of another modified deviceaccording to the invention;

Figure V is a vertical sectional view of still another modifieddeviceaccording to the invention;

Figure VI is a vertical sectional view of a drip and filter chamberaccording to the invention;

Figure VII is a vertical sectional view of a modified form of'theinvention;

Figure VIII is a fragmentary vertical sectional view of the upperportion of the device of Figure VII indicating its configuration whileit is being connected to a source of supply;

Figure IX is a fragmentary vertical sectional view of the lower end of adrip chamber indicating an alternative assembly for the bottomconnections; and

Figure X is a fragmentary vertical sectional view similar to Figure IXshowing another modification of the bottom assembly.

The device shown in Figure I comprises a cylindrical hollow body portionor a main tube portion 12 of resilient plastic material, and ispreferably transparent, or at least translucent. A thimble or cup shapedfilter screen 20 is frictionally held in the tube 12 in close proximityto the end adjacent the cup opening. The ends of the tube 12 are closedby resilient plastic annuli 16 which are cemented into place. A stiffplastic cannula is cemented into one of the annuli 16, and a length ofresilient plastic tubing 14 is cemented into the other annulus. Ifdesired a length of resilient plastic tubing can be secured in the upperannuli l6 and the cannula 10 connected to the outer end of the saidlength of plastic tubing. It is preferable to have the cannula 10communicating with the cup side of the screen 20, as shown, rather thana configuration such as when the tubing 14 and the cannula 10 arereversed.

The tubing 14 is of a suitable length, for example, about 2 feet, toallow either direct transfusion from the filter cell or through a flowcontrol apparatus, such as a Murphy drip tube. A fitting is connected tothe end of the tubing 14 to allow connection of the filter cell withother apparatus, such as an injection needle. As shown, a male Luerfitting 22 is connected to the end of the tubing 14, however, othertypes of fittings may be used as for instance, a female Luer, ahypodermic cannula, etc.

In use, the device of Figure I can be connected directly to atransfusion bottle, containing for instance blood, by

inserting the stiff cannula 10 through a rubber stopper sealing thebottle. The filter cell is then connected directly to the patient orthrough a metering device through the connection 22, as for instance aneedle connected to the Luer 22 into a receiving patients vein.

The main tube portion 12, being resilient, is capable of collapsingunder external pressure so as to act as a pressure bulb.

This is important especially in blood transfusion where the bloodfrequently clots even though an anticoagulant United States Patent 0plug the withdrawing cannula, however, using a device according to theinvention, the tube portion 12 may be squeezed (indicated in dottedlines in Figure V) to exert pressure back through the cannula 10,thereby unplugging the cannula. Obviously, to prevent the pressure fromentering the patients vein, the tubing 14 should be closed whilecollapsing the cell.

In the device of Figure III a plastic tubing 18 is sealed, completelyclosing one end of the tubing. The tubing 18 is punctured with aplurality of holes 32 forming a type of sieve or foraminated filtermedium. The plastic tubing 18 is then inserted into the annulus 16 andcemented in place so that all the perforations are on one side of theannulus. The annulus 16 is then cemented into place in the main body 12with the perforated tubing portion inside the main tube 12. The otherend of the main tube 12 is enclosed as in Figure I with an annulus 16cemented in place, carrying a stiff cannula 10.

The device of Figure IV has a larger diameter tubing with a sealed end42 and perforations 44 sealed into a countersunk annulus 46. A length oftubing 14 is sealed in the annulus 46 communicating with the interior ofthe sieve-like portion 40. The annulus 46 is inserted into the main tubebody 12 and cemented into place, having the sieve 40 inside the maintube body 12. The other end of the filter cell is enclosed by theannulus 16 with the stiff cannula 10 cemented therein.

The device in Figure V has a length of tubing 14 sealed in an annulus16, and having one end 50 a short distance therethrough. A small wovenplastic bag 52 is fastened on the end 50. The annulus 16 is cementedinto the main tube body 12, with the filter bag 52 enclosed in saidtube. The other end of said tube 12 is closed with an annulus 16 havinga stiff cannula 10 cemented therein.

A filter cell with the filter integral with the discharge port or outletas shown in Figures III, IV, and V may have the cannula 10 extend ashort distance through the annulus 16 to the interior of tube 12, tofunction as a drip tube, to aid in metering the flow.

Any blood clots which form in devices having the filter integral withthe discharge port, tend to settle, leaving the upper part of theforaminated tube or filter free from clots. Furthermore, with theplastic filter medium cemented in place there is little danger ofdisplacing the filter or impairing its functions.

The material of the main tube 12 is of the type commonly referred to inthe trade and in the technological literature as commercial plastics.These are solid products of polymerized organic molecules. Such plasticsare suitable for use in medical work where they must contact fluids thatmay subsequently enter the blood stream. Of course, stainless steel,glass or other rigid materials are also suitable, but they lack theproperties necessary to achieve the objects of the invention, whichinclude flexibility and resilience combined, so that the distortion ofthe tube can exert a pumping action.

In the embodiment of the invention selected for illustration in FigureVI, the sight or drip chamber comprises a barrel of resilient plastic,such as a vinyl type. The main wall of the barrel is resilient andflexible but under its own weight it retains the configurationillustrated. Only slight forces are necessary to collapse it, and it canbe collapsed, folded, and doubled under repeatedly without materialinjury or permanent distortion.

At its upper end the barrel or cylindrical hollow body of Figure VI isintegrally united to a resilient end closure means comprising a reducermember 62 which reducer tapers in to define a neck 64. Bonded in theneck 64 is a relatively rigid intake cannula 66 having a sharp beveledend 68 adapted to pierce or be inserted into, a

has been used. The clots, if large enough, will seal or rubber outletplug or seal of a suitable source of therapeutic fluid. The cannula 66also preferably extends down inside the barrel so that the flow willfall from it and be easily seen. As delivered from the factory insterilized condition ready for use the upper end of the cannula 66carries a removable cover 70.

The cannula 66 is relatively rigid and of suflicient structural strengthto penetrate the seal of the source of supply, but a substantial axialforce is necessary to effect such penetration. Because the barrel isextremely flexible, it is easy for the user in practicing the insertionof the cannula, to pinch the sides in as indicated by the arrows 76 inFigure VIII so that a thumb and forefinger can get a firm grip directlyagainst the cannula except for the intervening thickness of flexiblematerial. This contributes materially to quickness and ease of Operationin assemblying the parts.

Referring again to Figure VI the barrel 60 is molded and its lower endclosure means includes the bottom neck 78 enlarged at 80 to define anannular shoulder facing upward and enlarged again at 82 to merge withthe side wall of the barrel forming in effect an internal rabbet. Afilter 84 is inserted in the rabbet with its lower end in abutment withthe annular face 80 and bonded in place. The filter 84 illustrated is acylindrical tube of resilient plastic provided with suitableforaminations 86 to permit fiuids to pass through, while retaining bloodclots or other solid bodies large enough to cause trouble farther on.Below the shoulder 80, the neck 78 receives the upper end of thedelivery tube 88 which may be of desired length and ends in a terminalfitting 90 for convenient connection to a hypodermic needle or toanother container.

In completing an assembly according to Figure VI the barrel 60 is bondedto the tube 88 and to filter 84 in any desired sequence. Then the cap 62is bonded on the cannula 66; the cap 62 and the barrel 60 are bondedtogether; the protective cover 70 is put on; and the assembly is readyto be sterilized.

In the embodiment of Figure VII the barrel 72 and neck 74 are formed inone piece and at the lower end the bottom cap 92 which may comprise areadily flexible cup-shaped form having its concave side facing into thesaid barrel completes the connection to the delivery tube 96. The neck94 is bonded to the delivery tube 96 and the delivery tube extends uthrough the neck and into the chamber, and supports the filter 84 whichmay, if desired, be identical with that in Figure VI or of a differentsize.

In assembling a unit according to Figure VII the cannula 66 is bondedwith the barrel 72. The cap 92 is bonded on the tube 96. Then the filter84 is bonded on the same tube 96 and finally the barrel 72 is bondedwith the cap 92.

Referring now to Fi ure IX, the bottom cap 98 has a relatively long neck100. The filter 102 may be thrust into the neck from above and bonded inplace. Then the discharge tube 104 is similarly assembled. Thiscompletes an assembly ready for attachment to the barrel 72 of FigureVII.

Referring now to Figure X the bottom cap 106 has a shorter neck 108 andthe filter 110 has a long neck extending down beyond the neck 108. Thedelivery tube 112 is telescoped over the filter tube 110 and slides upuntil it comes into abutment with the neck 108. This completes a bottomassembly ready for attachment to the barrel 72.

It will be obvious that the drip chamber and delivery tube of Figures VIto X is suitable for use in direct connection with a penetrablecontainer closure or with any other source of supply connectable to thecannula 66. When using in direct connection with a container closure,the recommended procedure is to close the delivery tube at the exit endof the drip chamber and thrust the cannula 66 downward through thesealing diaphragm of the container closure to open communication withthe source of supply. The parts are then inverted, but no appreciableamount of fiuid will enter the chamber because the air in the chamberprevents it. The user now contracts the chamber by squeezing it a littleand a portion of the air in the chamber will rise through the cannula 66and bubble up through the liquid above it, since the inlet cannulaserving as an inlet tube has a constant effective volume less than theavailable variation of the chamber volume. When the pressure is releasedthe chamber expands and an equal volume of liquid will move down intothe chamber. In this way the user pumps the air out of the chamber alittle at a time and replaces it with liquid until the liquid is at thelevel desired, which should be just above the top of the filter, leavinga substantial clearance or space between the upper surface of the liquidand the lower end of the cannula 66.

The clamp 79 or other closure in the delivery tube closely adjacent thechamber is now partly opened and a body of liquid will move down thetube and expel the air in the tube. The fitting is connected fordelivery and the rate of flow can be observed by watching the liquidfalling from the cannula 66 and adjusted by constricting the tube 88.

In the use of such equipment it occasionally happens that a blood clotor other obstruction blocks the inlet end of the cannula 66. With theequipment of the invention the operator merely closes the tube 88 closeto the chamber 60 and squeezes the chamber to dislodge the clot. Withthe rigid drip chamber of the prior art, it is usual to move the bottlearound vigorously to agitate the contents and try to dislodge the clotin that way. It is also possible to constrict the tube 88 remote fromthe chamber and collapse a considerable length of it by squeezing it inone hand to develop the pumping action but the pumping action is muchmore conveniently and effectively obtainable with equipment according tothe invention.

It not infrequently happens, especially during somewhat prolongedadministration, or as a result of manipulation to dislodge a blood clot,that the liquid level in the drip chamber gets too hi h so that theoutlet of the cannula 66 is masked and it is impossible to observe therate of flow. With the rigid drip chamber of the prior art, thiscondition, commonly referred to as a flooded drip chamber, usuallynecessitated taking the apparatus to pieces more or less and startingover again.

When a flooded drip chamber is encountered with apparatus according tothe invention, the user merely closes the delivery tube close to thedrip chamber and inverts the drip chamber and the bottle or other sourceof supply so that the chamber is above the cannula. In this position theliquid in the source of supply will move away from the lower end of thecannula 66 and an air space will surround that lower end. There willalso be an air space in what is now the top of the drip chamber but noneof that air will work into the delivery tube because the delivery tubeis closed.

With the parts in this condition the user need only pump liquid out ofthe chamber by squeezing it, to have the liquid replaced by air when thepressure is released. In this way the drip chamber can be partially orcompletely emptied of liquid and refilled with air. Then the dripchamber and its bottle can be turned the other end up once more and ifthe liquid level in the drip chamber is lower than that desierd air canbe pumped out of the drip chamber and the unit is again functioningcorrectly. All the manipulations for reconditioning a flooded dripchamber can be performed by an experienced user in less time than ittakes to read this description.

The attribute described as resilience is intended to involve thecapacity of sustaining great changes in shape and consequently in thevolume of the resilient chamber or hollow body, such as the oneillustrated in Figure VIII, without rupture or objectionable permanentalteration in the shape assumed after a momentary stress is removed, asdistinguished from the amount of energy stored in the temporarilydeformed shape or the force required to achieve the deformation, both ofwhich are comparatively small in materials of the type described.

In the several embodiments of the invention illustrated it should beunderstood that, if desired, the filter means or the cannula means canbe omitted without departing from the broad invention illustrated anddescribed herein.

The bonding referred to is of a type generally known in this art, andper se, forms no part of this invention. Briefly, one of the parts to beunited is coated or dipped in a fluid having a mild solvent action onthe material of which the parts are made, and then the parts arejuxtaposed in the desired position and let stand. The mechanical aspectof the operation is substantially identical with gluing, but theresulting union seems to leave practically no interface, but asubstantial homogeneity extending through the mass, so that the materialforming the joint is of equal strength with the rest of the material,and the joint itself even a little stronger than the rest of theassembly because of its greater thickness.

This application is a continuing application of the inventors co-pendingapplications Serial No. 119,645, filed October 5, 1949, and Serial No.128,549, filed November 21, 1949, both now abandoned.

Others may readily adapt the invention for use under various conditionsof service by employing one or more of the novel features disclosed orequivalents thereof.

As at present advised with respect to the apparent scope of myinvention, I desire to claim the following subject matter.

1. A filter cell for venoclysis apparatus, comprising In combination:capable of being partially collapsed when external pressure is appliedthereto to effect a substantial change 1n the volume of the said hollowbody and returning to its original form when the pressure is released; afilter element in said body; end closure means at each end of said bodyhaving a passage therethrough; a tubular inlet means communicating withthe interior of said body secured to and projecting from one of the saidclosure means for communication with a source of liquid; and tubulardelivery means communicating with the interior of said body secured toand projecting from the other of the said closure means for dischargingliquid from the said body; said body when compressed after stopping theflow of fluid in the tubular delivery means effecting a back-flowthrough the said tubular inlet means, thereby facilitating dislodgingobstructions in the said tubular inlet means.

2. A venoclysis apparatus, comprising in combination: a deformable,cylindrical, hollow body capable of being partially collapsed whenexternal pressure is applied thereto and returning to its original formwhen the pressure is released; a filter element in said body; endclosure members at each end of said body having a passage therethrough;a cannula means communicating with the interior of said body through oneof the closure members for communication with a source of liquid; andtubular delivery means communicating with the interior of said bodysecured to and projecting from the other of the said closure members fordischarging liquid from the said body; said body when compressed afterstopping the flow of fluid in the tubular delivery means eflecting aback-flow through the cannula, thereby facilitating dislodgingobstructions in the said cannula.

3. A filter cell for venoclysis apparatus, comprising in combination: adeformable, cylindrical, hollow body capable of being partiallycollapsed when external pressure is applied thereto and returning to itsoriginal form when the pressure is released; end closure members at eachend of the said body having a passage therethrough; a cannulacommunicating with the interior of said body secured to and projectingfrom one of the said closure members for communication with a source ofliquid; and a tubular delivery means communicating with the interior ofsaid body secured to and projected from the other of said closuremembers for discharging liquid from the said body; a tubular section offoraminated material extending within said body and being secured to theclosure member remote from said cannula; said section being between theinterior of said body and the tubular delivery means, whereby the saidtubular section filters the liquid being discharged from said body; saidbody when compressed after stopping the flow of fluid in the tubulardelivery means etfecting a back-flow through the said cannula, therebyfacilitating dislodging obstructions in the said cannula.

4. A filter cell for venoclysis apparatus, comprising in combination: adeformable, cylindrical, hollow body capable of being partiallycollapsed when external pressure is applied thereto and returning to itsoriginal form when the pressure is released; end closure members at eachend of the said body having a passage therethrough; a cannulacommunicating with the interior of said body secured to and projectingfrom one of the closure members for communication with a source ofliquid; a tubular delivery means connecting the interior of said bodysecured to and projected from the other of said closure members fordischarging liquid from the said body; and a section of foraminatedmaterial extending within said body and being secured to the closuremember adjacent the said cannula; said section being interposed betweenthe said cannula and the tubular delivery means, whereby the saidtubular section filters the liquid being introduced into said body; saidbody when compressed after stopping the flow of fluid in the tubulardelivery means effecting a back-flow through the said cannula, therebyfacilitating dislodging obstructions in the said cannula.

5. A filter cell for venoclysis apparatus, comprising in combination: adeformable, cylindrical hollow body capable of being partially collapsedwhen external pressure is applied thereto and returning to its originalform a deformable, cylindrical, hollow body when the pressure isreleased; end closure members at each end of the said body having apassage therethrough; a cannula communicating with the interior of saidbody secured to and projecting from one of the closure members forcommunication with a source of liquid; a tubular delivery meanscommunicating with the interior of said body secured to and projectedfrom the other of said closure members for discharging liquid from thesaid body; and a tubular section of foraminated material closed at itsinterior end and being coaxial with the said tubular delivery means,said section being interposed between the said cannula and the tubulardelivery means, whereby the said tubular section filters the liquidbeing discharged from said body; said body when compressed afterstopping the flow of fluid in the tubular delivery means effecting aback-flow through the said cannula, thereby facilitating dislodgingobstructions in the said cannula.

6. A filter cell for venoclysis apparatus, comprising in combination: adeformable, cylindrical, hollow body capable of being partiallycollapsed when external pressure is applied thereto and returning to itsoriginal form when the pressure is released; end closure members at eachend of the said body having a passage therethrough; a cannulacommunicating with the interior of said body secured to and projectingfrom one of the closure members for communicating with a source ofliquid; and a tubular delivery means communicating with the interior ofsaid body secured to and projecting from the other of said closuremembers for discharging liquid from the said body; and a filterextending inside the said body in open axial communication with the saidtubular delivery means, whereby the said tubular section filters theliquid being discharged from the said body; said body when compressedafter stopping the flow of fluid in the tubular delivery means effectinga back-flow through the said cannula, thereby facilitating dislodgingobstructions in the said cannula.

7. A drip chamber unit for administration of fluids comprising, incombination: a chamber proper; an inlet drip tube protruding into theinterior contour of said chamber, whereby, when said chamber ispositioned with said inlet at the top, and contains gas from the topdown to a level below the lower end of said inlet, the fall of enteringliquid from said inlet affords an indication of the rate of flow ofliquid through said chamber; said chamber being sufliciently transparentto permit visual observation of the falling liquid and the adjustment ofthe liquid level in the same chamber; and an outlet tube communicatingwith said chamber remote from said inlet tube; said chamber having aflexible, resilient wall for varying the eifective volume of saidchamber; said inlet tube having a constant efifective volume less thanthe variation of the chamber volume; said outlet tube adapted to beingclosed adjacent said chamber; whereby, with said inlet uppermost, afluid in said chamber of low specific gravity may be expelled throughsaid inlet and replaced with heavier fluid, by successive contractionand expansion of said chamber, with the inlet lowermost, the samemanipulation will expel a heavier fluid and replace it with a lighterone. 7

8. A drip chamber for administration of fluids, comprising, incombination: a chamber proper; an inlet drip tube protruding into theinterior contour of said chamber, whereby, when said chamber ispositioned with said inlet at the top, and contains gas from the topdown to a level below the lower end of said inlet, the fall of enteringliquid from said inlet affords an indication of the rate of flow ofliquid through said chamber; said chamber being sufliciently transparentto permit visual observation of the falling liquid and the adjustment ofthe liquid level in the said chamber; and means defining an outletpassage of substantially smaller diameter than said chambercommunicating with said chamber remote from said inlet tube and adaptedto being closed adjacent said chamber; said chamber having resilientflexible walls, whereby external pressure momentarily reduces theeffective volume of said chamber; said inlet tube having a constantefiective volume less than the available variation of the chambervolume; whereby fluid within said chamber is readily expelled from saidchamber.

9. A drip chamber unit for intravenous administration of fluids,comprising, in combination: a flexible plastic body having a mainportion of relatively large diameter, at least one end of said mainportion being open; the other end of said main portion being closed byan end closure having an extending neck of relatively small diameter; acap member having a portion telescoped with the large end of said bodyand an extending neck portion of relatively small diameter coaxial withthe said body; said body and cap member being bonded together into anintegral whole; a relatively rigid cannula integrally associated withthe said cap member and projecting interiorly of the said body andexteriorly beyond said neck; the exterior end of said cannula beingadapted to enter a supply container; the interior end of said cannulabeing spaced from said body, whereby liquid moving downwardly out of theinterior end of said cannula can be visually observed; said body beingsufliciently transparent to permit visual observation; and an externaldelivery tube associated with the said extending neck opposite saidcannula.

10. A drip chamber unit for intravenous administration of fluids,comprising, in combination: a flexible plastic body having a mainportion of relatively large diameter, one end of said main portion beingopen; the other end of said main portion being closed by an end closurehaving an extending neck of relatively small diameter; a cap memberhaving a portion telescoped with the large end of said body and anextending neck of relatively small diameter coaxial with the neck ofsaid body, said body and cap member being bonded together into anintegral whole; a relatively rigid cannula integrally associated withone of said necks and projecting interiorly inside said body andexteriorly beyond said neck; the exterior end of said cannula beingadapted to enter or penetrate a supply container; the interior end ofsaid cannula being spaced from said body, whereby liquid movingdownwardly out of the interior end of said cannula can be visuallyobserved; said body being sufliciently transparent to permit visualobservation; and an external delivery tube associated with the neckopposite said cannula, said body at least adjacent said cannula beingsufliciently transparent to permit visual observation thereof and beingsufficiently flexible to permit the operator to collapse it, andsufficiently resilient to return to substantially its original shapeafter temporary collapse.

A drip chamber unit for intravenous administration of fluids comprising,in combination: a flexible resilient plastic body having a main portionwith a relatively large diameter; one end of said main portion beingopen, the other end of said main portion being closed by an end closureportion having a relatively small diameter extending neck; a cap memberhaving a portion telescoped with the large end of said body; and anextending neck of relatively small diameter coaxial with the neck ofsaid body; said body and cap member being bonded together into anintegral whole; a relatively rigid cannula integrally associated withone of said necks and projecting interiorly of the said body andexteriorly beyond said neck; the exterior end of said cannula beingadapted to enter a supply container; the interior end of said cannulabeing spaced from said body; said body being sufliciently transparent topermit visual observation of its interior; and an external delivery tubeassociated with the neck opposite said cannula.

12. A drip chamber unit for intravenous administration of fluidscomprising, in combination: a flexible plastic body having a mainportion of relatively large diameter; and extending end closure neckportions of relatvely small diameter at both ends; a cannula permanentlybonded in one of said neck portions and projecting interiorly insidesaid body; an external delivery tube associated with the other of saidneck portions opposite said cannula; and an interiorly extending tubularfilter associated with the said other of the neck portions opposite saidcannula.

13. A drip chamber unit for intravenous administration of fluidscomprising, in combination: a flexible plastic body having a mainportion of relatively large diameter; and extending necks of relativelysmall diameter at both ends; a cannula permanently bonded in one of saidnecks and projecting interiorly inside said body; an external deliverytube associated with the neck opposite said cannula; and an interiorlyextending tubular filter associated with the neck opposite said cannula.

14. A drip chamber unit for intravenous administration of fluids,comprising, in combination: a flexible plastic body having a mainportion of relatively large diameter; and extending necks of relativelysmall diameter at In uu both ends; a cannula permanently bonded in oneof said necks and projecting interiorly inside said body; an externaldelivery tube associated with the neck opposite said cannula; and aninteriorly extending tubular filter associated with the neck oppositesaid cannula; said neck being integrally bonded to said delivery tube;said delivery tube extending inside said body and being bonded to andsupporting said filter.

15. A drip chamber for intravenous administration of fluids, comprising,in combination: a flexible plastic body having a main portion ofrelatively large diameter; and extending nccks of relatively smalldiameter at both ends; a cannula permanently bonded in one of said necksand projecting interiorly inside said body; an external delivery tubeassociated with the neck opposite said cannula; and an interiorlyextending tubular filter associated with the neck opposite said cannula;said neck being integrally bonded to said filter; said filter extendingthrough and beyond said neck; said delivery tube being telescoped withand integrally bonded to the projecting portion of said filter.

16. A drip chamber unit for intravenous administration of fluids,comprising, in combination: a flexible plastic body having a mainportion of relatively large diameter; and end closures having extendingnecks of relatively small diameter at both ends; a cannula permanentlybonded in one of said end closures and projecting interiorly inside saidbody; an external delivery tube associated with the other of said endclosures opposite said cannula; and an interiorly extending tubularfilter associated with the said other of the end closures opposite saidcannula; said other of the end closures being integrally bonded to saidfilter.

17. In a drip tube for venoclysis equipment, comprising a resilient,elongated, hollow body, the improvement comprising; a cannula secured toand projecting from one end of said body, said cannula communicatingwith the interior of said body and having a sharpened end facing awayfrom said body for insertion through a soft rubber or similar containerclosure element to establish communication of such container with saidbody, said cannula extending into said body sufliciently to be capableof being gripped between opposite wall portions of said body undercompression between the fingers of a persons hand, thereby to facilitateinsertion of said cannula into a container closure as aforesaid.

18. In a drip tube for venoclysis equipment, the improvement comprising;a resilient, elongated, hollow body, a cannula secured to and projectingfrom one end of said body, said cannula communicating with the interiorof said body and having a sharpened end facing away from said body forinsertion through a soft rubber or similar container closure element toestablish communication of such container with said body, the endportion of said body to which said cannula is secured as aforesaid beingof thin walled, readily flexible cup-shaped form having its concave sidefacing into said body, said cannula extending into said bodysufficiently to be capable of being gripped between opposite wallportions of said end closure and the adjacent end portion of said bodyunder compression between the fingers of a persons hand, thereby tofacilitate insgrtion of said cannula into a container closure asaforesai 19. A venoclysis apparatus comprising an elongated tubular bodyhaving end closures on its opposite ends, said body being made of soft,elastic, plastic material permitting said body to be collapsedtransversely, said body being sufiiciently transparent to permit visualobservation of liquid flow therein, at least one of said end closureshaving a cap-like portion fitting telescopically with an end portion ofsaid body, both of said end closures having openings extendingtherethrough for receiving inlet and outlet conduits in communicationwith the opposite end portions of said body and at least one of said endclosures having associated therewith a cannula for connection to a fluidsupply container, and at least one of said end closures embodying a wallportion which is of thickness approximating that of said body wall so asto be readily flexible and collapsible as an incident to collapsing ofsaid body transversely as aforesaid.

20. A venoclysis apparatus comprising an elongated tubular body havingend closures on its opposite ends, said body being made of soft,elastic, plastic material permitting said body to be collapsedtransversely, said body being sufliciently transparent to permit visualobservation of liquid flow therein, at least one of said end closureshaving a cap-like portion fitting telescopically with an end portion ofsaid body, both of said end closures having openings extendingtherethrough for receiving inlet and outlet conduits in communicationwith the opposite end portions of said body and at least one of said endclosures embodying a wall portion which is of thickness approximatingthat of said body wall so as to be readily flexible and collapsible asan incident to collapsing of said body transversely as aforesaid.

21. A drip tube for venoclysis equipment, comprising a flexible plastictubular body having end closures provided with reduced diameterextensions at both ends, a cannula seated in one of said end closuresand projecting inside said body, a delivery tube seated in the other ofsaid end closures, and a filter member also seated in said other of saidend closures and extending into said tubular body.

22. A drip tube for venoclysis equipment, comprising an elongatedflexible, resilient hollow body having end closure means at the oppositeends thereof, a cannula seated in one of said end closure meansextending into the inside of said body and projecting outwardlytherefrom for connection to a fluid supply container, 21 delivery tubeassociated with the other of said end closure means and extendingoutwardly from said body, and a filter member extending within saidbody.

23. A drip tube for venoclysis equipment, comprising an elongatedflexible, resilient hollow body having end closure portions, a cannulaassociated with one of said end closure portions for connection to afluid supply container, a length of relatively rigid tubing extendinginto the inside of said body in communication with the said cannula, afilter tube associated with the other of said end closures and extendingtherethrough and in opposite directions into said body; and a flexibledischarge tube extending outwardly from the said other of the endclosures.

24. A drip tube for venoclysis equipment, comprising an elongated,flexible, resilient hollow body having end closure portions, a cannulaassociated with one of said end closure portions, extending into theinside of said body and projecting outwardly therefrom for connection toa fluid supply container, a filter tube associated with the other ofsaid end closures and extending therethrough and in opposite directionsinto said body and outwardlv therefrom, and a discharge tube telescopedover said outwardly projecting filter tube portion.

25. A drip tube for venoclysis equipment comprising an elongatedflexible resilient hollow body having end closure means at the oppositesociated with one of said end closure means extending into the inside ofsaid body and projecting outwardly therefrom for connection to a fluidsupply container, a delivery tube associating with the other of said endclosure means and extending outwardly from said body, and z a filtermember within said body seated on and supported by the said other ofsaid end closure means.

26. A drip tube for venoclysis equipment, comprising, an elongatedflexible resilient hollow body having end closure means at the oppositeends thereof, a relatively rigid tubular member associated with one ofsaid end closure means extending into the inside of said body andprojecting outwardly therefrom for communication with a fluid supplycontainer, a delivery tube associated with the other of said end closuremeans and extending outwardly from said body, and a filter member withinsaid ody.

27. A drip chamber unit for administration of fluids from a containerhaving a penetrable container closure ends thereof, a cannula ascomprising, in combination: a flexible resilient plastic body having amain portion with a relatively large diam eter the effective volume ofwhich is variable upon application of external pressure thereto andcapable of returning to its original volume without permanentdeformation upon removal of said pressure and which has wall portionspermitting the observation of the falling drops of liquid through theinterior thereof and the adjustment of the liquid level therein by theapplication of said external pressure thereto; one end of said mainportion being provided with an end closure portion having an outwardlyextending cannula adapted for unobstructed communication with theinterior of said container through the said penetrable closure and aninwardly projecting drip forming tube extending into and spaced from theinterior of the said body, the other end of said main portion beingclosed by a second end closure portion having a relatively smalldiameter outlet passage defined thereby; and an external delivery tubeassociated with the said outlet passage; said body, cannula, drip tube,and end closure portions being permanently formed into an integralwhole; the said cannula having together with the said drip tube aconstant eflective volume less than the available variation of saidbody; whereby, with the said inlet uppermost, a fluid in said containerof low specific gravity is expelled through said inlet and replaced withheavier fluid by successive contraction and expansion of said chamber,and with the inlet lowermost, the same manipulation will expel a heavierfluid and replace it with a lighter fluid.

28. A drip chamber for venoclysis equipment, comprising a tubularflexible resilient hollow body having end closure portions, a relativelyrigid cannula member of substantially smaller diameter than the saidhollow body associated with one of said end closure portions extendinginto the inside of said body forming a drip tube within said body andprojecting outwardly therefrom for communication with a fluid supplycontainer, and a delivery tube of substantially smaller diameter thanthe said hollow body having the inlet thereto spaced below the end ofthe said cannula associated with the other of said end closure portionsand extending outwardly in the opposite direction from said body, saidbody being also sufficiently transparent to permit the observation ofthe drops formed and the adjustment of the liquid level within the saidhollow body.

References Cited in the file of this patent UNITED STATES PATENTS768,951 Rawsen Aug. 30, 1904 1,392,454 Seelman Oct. 4, 1921 1,607,561Pittenger Nov. 16, 1926 1,973,845 Chenoweth Sept. 18, 1934 2,138,936Osterberg Dec. 6, 1938 2,168,270 Paisley et al Aug. 1, 1939 2,186,987Nesset Jan. 16, 1940 2,315,109 Cutter Mar. 30, 1943 2,328,569 McGawSept. 7, 1943 2,341,114 Novak Feb. 8, 1944 2,353,153 Ferrel July 11,1944 2,362,537 Butler Nov. 4, 1944 2,473,153 Lager June 14, 19492,489,966 Laure et al Nov. 29, 1949 2,515,470 Prytz July 18, 1950FOREIGN PATENTS 165,283 France Nov. 10, 1884 573,611 Great Britain Nov.28, 1945

